ETEKOS experimental ecological system

The problem of changes in the ecology resulting, for example, in increases in water temperature because of discharges from large thermal power plants is considered. An experiment creating a model of such an ecological system is described

Towards the electron EDM search: Theoretical study of HfF+

We report first ab initio relativistic correlation calculations of potential curves for ten low-lying electronic states, effective electric field on the electron and hyperfine constants for the ^3\Delta_1 state of cation of a heavy transition metal fluoride, HfF^+, that is suggested to be used as the working state in experiments to search for the electric dipole moment of the electron. It is shown that HfF^+ has deeply bound ^1\Sigma^+ ground state, its dissociation energy is D_e=6.4 eV. The ^3\Delta_1 state is obtained to be the relatively long-lived first excited state lying about 0.2 eV higher. The calculated effective electric field E_eff=W_d|\Omega| acting on an electron in this state is 5.84*10^{24}Hz/(e*cm)Comment: 4 page

Configuration interaction calculation of hyperfine and P,T-odd constants on ^{207}PbO excited states for the electron EDM experiments

We report first configuration interaction calculations of hyperfine constants A_\parallel and the effective electric field W_d acting on the electric dipole moment of the electron, in two excited electronic states of ^{207}PbO. The obtained hyperfine constants, A_\parallel = -3826 MHz for the a(1) state and A_\parallel = 4887 MHz for the B(1) state, are in very good agreement with the experimental data, -4113 MHz and 5000 \pm 200 MHz, respectively. We find W_d = -(6.1 ^{+1.8}_{-0.6}) 10^{24} Hz/(e cm) for a(1), and W_d = (8.0 \pm 1.6) 10^{24} Hz/(e cm) for B(1). The obtained values are analyzed and compared to recent relativistic coupled cluster results and a semiempirical estimate of W_d for the a(1) state.Comment: 6 pages, REVTeX4 style, submitted to Pthys.Rev.

Drug Agranulocytosis

The paper covers the problem associated with the wide availability and uncontrolled use of over-the-counter medicines, particularly analgesics, antipyretics, and anticatarrhal agents, which lead to the occurrence of adverse drug reactions and poisonings and to considerable economic and human losses. The mechanisms of the pathogenesis of drug agranu-locytosis due to the intake of nonsteroidal analgesics and the diagnosis and treatment of this disease are described in detail. The case presented by the authors clearly demonstrates that the possible development of life-threatening complications due to the use of even submaximal permitted doses of widely spread and available anticatarrhal drugs. Key words: antipyretics, analgesics, nonsteroidal anti-inflammatory drugs, drug agranulocytosis, trepanobiopsy, myelo-gram, intensive care unit

Towards the electron EDM search. Theoretical study of PbF

We report ab initio relativistic correlation calculations of potential curves and spectroscopic constants for four lowest-lying electronic states of the lead monofluoride. We also calculated parameters of the spin-rotational Hamiltonian for the ground and the first excited states including P,T-odd and P-odd terms. In particular, we have obtained hyperfine constants of the $^{207}$Pb nucleus. For the $^2\Pi_{1/2}$ state $A_\perp=-6859.6$ MHz, $A_\|=9726.9$ MHz and for the A$^2\Sigma^+_{1/2}$ $A_\perp=1720.8$ MHz, $A_\|=3073.3$ MHz. Our values of the ground state hyperfine constants are in good agreement with the previous theoretical studies. We discuss and explain seeming disagreement in the sign of the constant $A_\perp$ with the recent experimental data. The effective electric field on the electron $E_{eff}$, which is important for the planned experiment to search for the electric dipole moment of the electron, is found to be 3.3 * 10^{10} V/cm

On Nonperturbative Calculations in Quantum Electrodynamics

A new approach to nonperturbative calculations in quantum electrodynamics is proposed. The approach is based on a regular iteration scheme for solution of Schwinger-Dyson equations for generating functional of Green functions. The approach allows one to take into account the gauge invariance conditions (Ward identities) and to perform the renormalization program. The iteration scheme can be realized in two versions. The first one ("perturbative vacuum") corresponds to chain summation in the diagram language. In this version in four-dimensional theory the non-physical singularity (Landau pole) arises which leads to the triviality of the renormalized theory. The second version ("nonperturbative vacuum") corresponds to ladder summation and permits one to make non-perturbative calculations of physical quantities in spite of the triviality problem. For chiral-symmetrical leading approximation two terms of the expansion of the first-step vertex function over photon momentum are calculated. A formula for anomalous magnetic moment is obtained. A problem of dynamical chiral symmetry breaking (DCSB) is considered, the calculations are performed for renormalized theory in Minkowsky space. In the strong coupling region DCSB-solutions arise. For the renormalized theory a DCSB-solution is also possible in the weak coupling region but with a subsidiary condition on the value of $\alpha$.Comment: 31 pages, Plain LaTex, no figures. Journal version: some discussion and refs. are adde

An adaptive prefix-assignment technique for symmetry reduction

This paper presents a technique for symmetry reduction that adaptively assigns a prefix of variables in a system of constraints so that the generated prefix-assignments are pairwise nonisomorphic under the action of the symmetry group of the system. The technique is based on McKay's canonical extension framework [J.~Algorithms 26 (1998), no.~2, 306--324]. Among key features of the technique are (i) adaptability---the prefix sequence can be user-prescribed and truncated for compatibility with the group of symmetries; (ii) parallelizability---prefix-assignments can be processed in parallel independently of each other; (iii) versatility---the method is applicable whenever the group of symmetries can be concisely represented as the automorphism group of a vertex-colored graph; and (iv) implementability---the method can be implemented relying on a canonical labeling map for vertex-colored graphs as the only nontrivial subroutine. To demonstrate the practical applicability of our technique, we have prepared an experimental open-source implementation of the technique and carry out a set of experiments that demonstrate ability to reduce symmetry on hard instances. Furthermore, we demonstrate that the implementation effectively parallelizes to compute clusters with multiple nodes via a message-passing interface.Comment: Updated manuscript submitted for revie

Оптимизация ПДКВ у больных с острым респираторным дистресс-синдромом, вызванным прямыми и непрямыми повреждающими факторами

Objective: to study the clinical efficiency of undifferentiated and differentiated use of escalation and de-escalation procedures for optimizing positive end-expiratory pressure (PEEP) during mechanical ventilation in patients with acute respiratory distress syndrome (ARDS) resulting from direct and indirect damaging factors. Subjects and methods. During a prospective study, 24 examined patients (16 men, 8 women; their age was 22 to 65 years) with ARDS of different genesis were divided into 2 groups. Group A (n=11; 7 men, 4 women) and Group B (n=13; 9 men, 4 women) included patients with ARDS arising from both direct (gastric content aspiration, blunt chest injury with lung contusion, and acute bilateral bacterial pneumonia) and indirect (abdominal sepsis, severe nonthoracic injury, and acute massive blood loss) damaging factors. The results of treatment via differentiated or undifferentiated, according to the cause of ARDS, use of escalation and de-escalation procedures for PEEP optimization were assessed in Groups A and B patients. Results. The differentiated, according to the cause of ARDS, use of escalation and de-escalation procedures for PEEP optimization makes it possible to more effectively improve the parameters of pulmonary gas exchange and biomechanics and to reduce the length of respiratory support and stay in the intensive care unit, the incidence of ventilator-associated pneumonia, and mortality rates in patients with ARDS resulting from direct and indirect damaging factors. Conclusion. It is advisable to apply the differentiated, according to the cause of ARDS, approach to choosing escalation or de-escalation procedures to optimize PEEP in patients with ARDS of different genesis. Key words: acute respiratory distress syndrome, direct damaging factors, indirect damaging factors, mechanical ventilation, positive end-expiratory pressure, escalation PEEP optimization procedure, de-escalation PEEP optimization procedure, lung opening manoeuver.Цель исследования — изучение клинической эффективности не дифференцированного и дифференцированного применения эскалационного и деэскалационного способов оптимизации положительного давления в конце выдоха в условиях искусственной вентиляции легких у больных с острым респираторным дистресс-синдромом, развившимся вследствие воздействия прямых и непрямых повреждающих факторов. Материал и методы. 24 обследованных больных (16 мужчин, 8 женщин, возраст от 22 до 65 лет) с ОРДС различного генеза в ходе проспективного исследования были разделены на 2 группы. Группа А (я=11, 7 мужчин, 4 женщины) и группа B (n=13, 9 мужчин, 4 женщины) — больные с ОРДС, развившимся вследствие воздействия как прямых повреждающих факторов (аспирация желудочным содержимым, тупая травма груди с ушибом легких, острая двусторонняя бактериальная пневмония), так и непрямых повреждающих факторов (абдоминальный сепсис, тяжелая неторакальная травма, острая массивная кровопотеря). У больных групп А и В оценивали результаты лечения при дифференцированном и недифференцированном, в зависимости от причин развития ОРДС, применении эскалационного или деэскалационного способов оптимизации ПДКВ. Результаты. Дифференцированное, в зависимости от причин развития ОРДС, применение эскалационного и деэскалационного способов оптимизации ПДКВ позволяет более эффективно улучшить показатели газообмена и биомеханики легких, сократить продолжительность респираторной поддержки, пребывания в реанимационном отделении, частоты развития респиратор-ассоциированной пневмонии и летальность у больных с ОРДС, развившимся на фоне прямых и непрямых повреждающих факторов. Заключение. У больных с ОРДС различного генеза целесообразно использовать дифференцированный, в зависимости от причины развития ОРДС, подход к выбору эскалационного или деэскалационного способов оптимизации ПДКВ. Ключевые слова: острый респираторный дистресс-синдром, прямые повреждающие факторы, непрямые повреждающие факторы, искусственная вентиляция легких, положительное давление в конце выдоха, эскалационный способ оптимизации ПДКВ, деэскалационный способ оптимизации ПДКВ, прием «открытия» легких

Информативность индекса оксигенации при диагностике острого респираторного дистресс-синдрома

Objective: to study the informative value of the oxygenation index as a criterion for the diagnosis of acute respiratory distress syndrome (ARDS) of varying genesis. Subjects and methods. Seventy-two patients, including 27 women and 45 men, aged 19 to 65 years admitted to an intensive care unit for various diseases, in whom ARDS was diagnosed on the basis of the traditional criteria, were prospectively examined. The authors analyzed the causes of acute respiratory failure, the time course of changes in gas exchange and PaO2/FiO2, X-ray picture, and the time of respiratory support when respiratory and nonrespiratory treatments were performed. Results. After correction of the extrapulmonary causes of impaired gas exchange, optimization of respiratory support parameters, and use of aggressive artificial ventilation methods and nonrespiratory treatments, 45 (62.5%) of the 72 examinees diagnosed as having ARDS showed a considerable gas exchange improvement and a steady increase in the oxygenation index more than 300; thus, these patients stopped meeting the criteria of ARDS. Conclusion. The oxygenation index is a rather vulnerable sign of ARDS, the time course of changes in which depends on many pulmonary and extrapulmonary causes, which necessitates a comprehensive evaluation of the degree of lung injury, the causes and severity of respiratory failure and, evidently, the refinement and expansion of the criteria for establishing this diagnosis. Key words: acute lung injury, acute respiratory distress syndrome, acute respiratory failure, oxygenation index.Цель исследования . Изучение информативности индекса оксигенации, как критерия диагностики ОРДС различного генеза. Материал и методы. Проспективно обследовали 72 больных: 27 женщин и 45 мужчин, в возрасте от 19 до 65 лет, поступивших в ОРИТ с различными заболеваниями, которым на основании традиционных критериев был установлен диагноз ОРДС. Анализировали причины развития ОДН, динамику показателей газообмена и PaO2/FiO2, рентгенографической картины и сроков респираторной поддержки (РП) на фоне применения респираторных и не респираторных методов лечения. Результаты. Среди 72 обследованных больных с диагнозом ОРДС у 45 (62,5%) после коррекции внелегочных причин нарушений газообмена, оптимизации параметров респираторной поддержки, применения агрессивных методов ИВЛ и нереспираторных методов лечения удалось добиться существенного улучшения показателей газообмена и стойкого повышения индекса оксигенации более 300 — таким образом, эти больные перестали соответствовать критериям ОРДС. Заключение. Индекс оксигенации является достаточно уязвимым признаком ОРДС, динамика изменений которого зависит от многих легочных и внелегочных причин, что диктует необходимость комплексной оценки степени повреждения легких, причин развития и тяжести дыхательной недостаточности, и, по видимому, уточнения и расширения критериев постановки этого диагноза. Ключевые слова: острое повреждение легких, острый респираторный дистресс-синдром, острая дыхательная недостаточность, индекс оксигенации